Many fence designs have been used in the past for defining property boundaries, as protective devices to prevent entry and as a means of confining animals. These structures have included wood, metal, plastic and wire or cable fences. Prior fence structures have presented problems with respect to installation, strength and cost of the fencing material and repair. A number of fence designs have included the use of metal post and rail components in an effort to resolve problems as to these features. However, many arrangements for attachment of the rails to the posts have not provided a system which is both low cost and sufficiently rigid upon installation to withstand the normal, and on occasion extraordinary, use to which fencing is subjected in a agricultural, commercial and residential environment.
Examples of post and rail structures which have been used in the past include D. E. Daily, U.S. Pat. No. 3,822,053; J. Bouye, U.S. Pat. No. 3,902,703; R. W. Bright, U.S. Pat. No. 3,921,960; W. A. Soriero, Jr., U.S. Pat. No. 3,955,801; C. D. Totten, U.S. Pat. No. 4,007,919; J. D. Coleman, Jr., U.S. Pat. No. 4,140,298; K. T. Densen, U.S. Pat. No. 4,149,702 and Japanese Patent No. 52-49640. Although these patents describe various post and rail fence assemblies, the structures fail to provide a straightforward and rigid means of construction of the posts and rails and means for attachment of the rails to the posts. Further, these systems generally are complex in their structure, providing difficult structures for assembly and in many cases semi-permanent attachment which makes repair of fence structure or adjustment difficult, or impossible, without damage to the fence structure. In other of these designs, where a semi-permanent attachment is not provided, the attachment is not sufficient to withstand the use and wear encountered by fences used in a agricultural, commerical or residential applications.
Thus, a need has arisen for a fence structure which is rigid in its structure, provides for ease of assembly and repair, is aesthetically pleasing and economical to manufacture.